diff --git a/repos/system_upgrade/common/actors/initramfs/upgradeinitramfsgenerator/libraries/upgradeinitramfsgenerator.py b/repos/system_upgrade/common/actors/initramfs/upgradeinitramfsgenerator/libraries/upgradeinitramfsgenerator.py
index 7d1f2b7786..a06fd1efee 100644
--- a/repos/system_upgrade/common/actors/initramfs/upgradeinitramfsgenerator/libraries/upgradeinitramfsgenerator.py
+++ b/repos/system_upgrade/common/actors/initramfs/upgradeinitramfsgenerator/libraries/upgradeinitramfsgenerator.py
@@ -438,10 +438,10 @@ def _generate_livemode_initramfs(context, userspace_initramfs_dest, target_kerne
            '--kver', target_kernel_ver, '-f', userspace_initramfs_dest]
 
     # Add dracut modules
-    cmd += list(itertools.chain(*(('--add', module) for module in dracut_modules)))
+    cmd.extend(itertools.chain(*(('--add', module) for module in dracut_modules)))
 
     # Add kernel modules
-    cmd += itertools.chain(*(('--add-drivers', module.name) for module in initramfs_includes.kernel_modules))
+    cmd.extend(itertools.chain(*(('--add-drivers', module.name) for module in initramfs_includes.kernel_modules)))
 
     try:
         context.call(cmd, env=env)